That's according to a ranking security official in northern Lebanon. He spoke to the Los Angeles Times on condition of anonymity.

He said the weapon was a small explosive charge surrounded by nails and ball bearings, meant to inflict maximum casualties. The official said the explosive charge was concealed under a civilian vehicle and likely activated by remote control, just like the August blast.

“The perpetrator is one,” he said. "The same exact method and technique was used in the previous attack."

The August explosion came as President Michel Suleiman visited Syria in a landmark trip meant to reconcile the two countries.

The timing of Monday’s attack suggested that it was meant to derail confidence in the government and army just as Lebanon’s squabbling religious communities have begun easing tensions ahead of elections next spring, analysts said.

It came hours before parliament convened to discuss a new electoral law meant to improve the performance of a weak central government. Lebanese Prime Minister Fouad Siniora oversaw the signing of an agreement earlier this month meant to halt sporadic fighting in and near Tripoli between Sunni Muslims and members of Lebanon’s Alawite sect.

Lebanon’s Shiites, Sunnis, Christians and Druze agreed over the weekend to rip down provocative posters and political propaganda in a move aimed at cooling political tempers that brought the country to the brink of civil war last May.

Four of the dead were soldiers, as were about 17 of the 30 injured.

"This attack targeted the army in the first place," said the security official. "But at the same time, it’s against the new reconciliation and national unity."